Hello and welcome to the forum!,
The turbo could boost with the electronic actuator completely off/ disconnected from the car - it would boost and run normally up to the point that there was too much boost (usually at higher revs/ under a heavy load - eg when you were "booting" it) at which point the car would go into limp home mode - if you drove the car gentle enough/ changed up early with the minimum of throttle it may be ok (just don't go uphill!)
The actuator controls the VNT mech/ vanes via a control rod, these vanes direct exhaust gasses towards the turbine - it helps the turbo boost up from low revs and higher revs, and controlls the maximum boost pressure (there is no seperate wastegate, the VNT mech works like a wastegate)
The VNT mech/ variable vanes can get siezed/ the proper amount of travel can be reduced or the mech has a high resistance because the mech gets coked up with carbon from the exhaust - this can have a "knock-on" sffect on the actuator (puts the SWR up puts a high load on actuator motor/ control electronics/ a sticking mech can damage the actuator)
So you must make sure the VNT / vanes/ control rod are all working ok before you fix the actuator - the VNT may need to be removed/ decoked/ rebuilt, or replaced or at least checked/ loosened off
You used to have to buy the whole manifold/ turbo/ actuator from Ford, (at an extortionate price) but there are specalist repairers that repair actuators on an exchange basis, there is one part in the actuator that "burns out" 1st (i don't know which bit, im sure the reparers would not tell us - possibly the motor, or it could be a £1 component?) - you can pick up the actuators secondhand online.